Verdchiebung beim Zeichnen

[k-s]

import java.io.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

class LineRectOval
{
  public static void main(String args[])
  {new MyFrame("LineRectOval");}
}

class MyFrame extends JFrame implements ActionListener
{
  private Point a = null;
  private Point b = null;

  JButton bLine = new JButton("Line");
  JButton bRectangle = new JButton("Rectangle");
  JButton bOval = new JButton("Oval");
  
  JPanel zFlaeche = new JPanel(new GridLayout(1,1));
  JPanel panel = new JPanel();
  
  MyFrame(String s)
  {
    super(s);

    getContentPane().setLayout(new BorderLayout());
    panel.add(bLine); panel.add(bRectangle); panel.add(bOval);
    getContentPane().add(panel, BorderLayout.SOUTH);
    getContentPane().add(zFlaeche, BorderLayout.CENTER);

    zFlaeche.setBackground(Color.WHITE);
    zFlaeche.setBorder(BorderFactory.createLineBorder(Color.BLACK));

    bLine.addActionListener(this);bLine.setActionCommand("LINE");
    bRectangle.addActionListener(this);bRectangle.setActionCommand("RECTANGLE");
    bOval.addActionListener(this);bOval.setActionCommand("OVAL");
    
    addMouseListener(new MouseAdapter()
                                       {
                                         public void mouseClicked(MouseEvent e)
                                         {if(a==null){a = e.getPoint();} else{b = e.getPoint();}};
                                       });

    Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
    setLocation( (d.width-900)/2 , (d.height-900)/2 );
    setSize(900, 900);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setVisible(true);
  }
  
  public void actionPerformed(ActionEvent e)
  {
    if((a!=null)&(b!=null))
    {
      int obenlinks_x,obenlinks_y,breite,hoehe;
      obenlinks_x = (int)Math.min(a.getX(), b.getX());
      obenlinks_y = (int)Math.min(a.getY(), b.getY());
      breite      = (int)Math.abs(a.getX()-b.getX());
      hoehe        = (int)Math.abs(a.getY()-b.getY());

      if (e.getActionCommand().equals("LINE"))
         {zFlaeche.getGraphics().drawLine((int)a.getX(),(int)a.getY(),(int)b.getX(),(int)b.getY());}
      else
          if (e.getActionCommand().equals("RECTANGLE"))
             {zFlaeche.getGraphics().drawRect(obenlinks_x,obenlinks_y,breite,hoehe);}
          else
               if (e.getActionCommand().equals("OVAL"))
                  { int radius = (int)Math.sqrt((breite*breite)+(hoehe*hoehe));
                    zFlaeche.getGraphics().drawOval
                                                  ((int)a.getX()-radius,(int)a.getY()-radius,2*radius,2*radius);}
    }
    a = null; b = null;
  }
}

Bei mir verschieben sich alle Figuren auf der Zeichenfläche um paar Pixeln nach unten-rechts, habe keine Ahnung warum Ö_ö

 

[André Uhres]

Weil der MouseListener am Frame und nicht an der Zeichenfläche hängt:

package paint;
/*
 * LineRectOval2.java
 */
import java.awt.image.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class LineRectOval2 {
    public static void main(String args[]) {
        new MyFrame("LineRectOval2");}
}
class MyFrame extends JFrame implements ActionListener {
    private Point a = null;
    private Point b = null;
    private JButton bLine = new JButton("Line");
    private JButton bRectangle = new JButton("Rectangle");
    private JButton bOval = new JButton("Oval");
    private ZeichenFlaeche zFlaeche = new ZeichenFlaeche();
    private JPanel panel = new JPanel();
    private Image bildBuffer;
    private Graphics2D bildBufferGraphics;
    MyFrame(String s) {
        super(s);
        getContentPane().setLayout(new BorderLayout());
        panel.add(bLine); panel.add(bRectangle); panel.add(bOval);
        getContentPane().add(panel, BorderLayout.SOUTH);
        getContentPane().add(zFlaeche, BorderLayout.CENTER);
        zFlaeche.setBackground(Color.WHITE);
        zFlaeche.setBorder(BorderFactory.createLineBorder(Color.BLACK));
        bLine.addActionListener(this);bLine.setActionCommand("LINE");
        bRectangle.addActionListener(this);bRectangle.setActionCommand("RECTANGLE");
        bOval.addActionListener(this);bOval.setActionCommand("OVAL");
        Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
        setLocation( (d.width-900)/2 , (d.height-900)/2 );
        setSize(900, 900);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setVisible(true);
    }
    public void actionPerformed(ActionEvent e) {
        if((a!=null)&(b!=null)) {
            int obenlinks_x,obenlinks_y,breite,hoehe;
            obenlinks_x = (int)Math.min(a.getX(), b.getX());
            obenlinks_y = (int)Math.min(a.getY(), b.getY());
            breite      = (int)Math.abs(a.getX()-b.getX());
            hoehe        = (int)Math.abs(a.getY()-b.getY());
            if (e.getActionCommand().equals("LINE")) {
                bildBufferGraphics.drawLine((int)a.getX(),(int)a.getY(),(int)b.getX(),(int)b.getY());
            }else if (e.getActionCommand().equals("RECTANGLE")) {
                bildBufferGraphics.drawRect(obenlinks_x,obenlinks_y,breite,hoehe);
            }else if (e.getActionCommand().equals("OVAL")) {
                int radius = (int)Math.sqrt((breite*breite)+(hoehe*hoehe));
                bildBufferGraphics.drawOval((int)a.getX()-radius,(int)a.getY()-radius,2*radius,2*radius);
            }
            zFlaeche.repaint();
        }
        a = null; b = null;
    }
    class ZeichenFlaeche extends JPanel{
        public ZeichenFlaeche(){
            addMouseListener(new MouseAdapter() {
                public void mouseClicked(MouseEvent e) {
                    if(a==null){a = e.getPoint();} else{b = e.getPoint();}};
            });
        }
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            if(bildBuffer == null){
                //Bildpuffer erzeugen:
                int w = getWidth();
                int h = getHeight();
                bildBuffer = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
                bildBufferGraphics = (Graphics2D)bildBuffer.getGraphics();
                bildBufferGraphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                        RenderingHints.VALUE_ANTIALIAS_ON);
                bildBufferGraphics.setBackground(Color.WHITE);
                bildBufferGraphics.clearRect(0, 0, w, h);
                bildBufferGraphics.setColor(Color.BLACK);
            }
            //Bildpuffer malen:
            g.drawImage(bildBuffer, 0, 0, null);
        }
    }
}

________________________________________
Fahrt fort, einander zu ertragen und einander bereitwillig zu vergeben.

 

[k-s]

Dnake André!

 

[k-s]

Ooops =)

Danke!